Improvement in ventilators



i P. MIHAN.

VENTILATOR.

No..186,52. Patented J'an.9,1877.

the upper parts of the ventilator.

UNITED STATES PATENT Orrron PATRICK MIHAN, OF OAMBRIDGEPOBT,MASSACHUSETTS.

IMPROVEMENT IN VENTILATORS.

Specification forming part of Letters Patent No. 186,052, dated January9, 1877; application filed March 28, 1876.

To all whom it may concern:

Be it known that I, PATRICK MIHAN, of (Jambridgeport, in the county ofMiddlesex and State of Massachusetts, have invented certain new anduseful Improvements in Ventilators; and I do hereby declare that thefollowing is a full, clear, and exact description thereof, which willenable others skilled in the art to which it pertains to make and usethe same, reference being had to the accompanying drawing, and to theletters of reference marked thereon, which form a part of thisspecification.

In such drawing, Figure 1 denotes a side elevation, and Fig. 2 avertical and central section, of a ventilator constructed in accordancewith my invention. Fig. 3 is a transverse section taken on the line a;a: of Fig. 1.

My invention has reference to that class of devices applied to the topsof chimneys and ventiducts, in order to increase the draft or provide abetter ventilation of the building; and my invention consists in thepeculiar construction and arrangement of the parts, as hereinafteddescribed and claimed.

In the said drawing, A denotes the main ventilator or exhaust pipe,which is to be fixed to the top of the building or structure to beventilated. B B are two hollow truncated cones or conic frusta, whichare disposed around the pipe A, such frusta being united at their largerbases, the part B being furnished with one or more series ofopenings,at, extending entirely around the same, such part at its lower end beingclosed and soldered, or otherwise firmly affixed to the pipe A, andthereby affording a support, on which to rest In order to render theventilator more strong and durable, I employ an annular plate or ring,0, whose outer perimeter is connected with the upper end of the frustumB, its inner perimeter being soldered or firmly secured to the pipejustbelow its eduction end. This plate is formed with a series ofperforations, 1), ex-

tending entirely around it, in order to allow the air entering the partB to escape through the orifices b 11, such plate 0 serving to hold thefrustum B in firm connection with the pipe A, and thereby render theparts more firm and stable, so as to withstand the action of high winds,or instead of the plate 0 the upper part of the frustum B may extend upso as to impinge against and be soldered, or otherwise properly secured,to the pipe A, the series of perforations b b being formed in suchextended part of the frustum B. d d are series of vertical partitionsdisposed within the chamber of the parts B B, such serving to divide thesaid chamber into separate air-passages, by Which the currents of airare prevented from horizontal or lateral deflections, such partitionsalso serving to increase the firmness of the structure. D is a guard,which is affixed to the frustum B at or nearits top, such guard flaringoutwardly and extending a short distance above the eduction end of thepipe A, such guard extending around the series of holes b b, &c., andserving to diminish the outside pressure of the external air upon thecurrents rising through the orifices b as Well as upon the eduction endof the pipe A, whereby the air issuing from such orifices and pipe isallowed greater freedom of expansion, and thereby more readily escapesthrough the opening beneath the dome. E is the dome or deflecting cap,which is supported upon rods ffaffixed at their lower ends to the lowerfrustum B.

Having described my invention, what I claim is- 1. The combination, withthe pipe A, of the frustum B, provided with the perforated top orannular plate 0, as and for the purpose set forth.

2. In a ventilator, substantially as described, the combination, withthe pipe A and the frustum B, of the frustum B provided with an annularperforated top or plate 0, and the guard D, the whole being constructed,combined. and arranged as and for the purpose set forth.

3. The improved ventilator, as described, consisting of the pipe A, thefrusta B B, the guard D, and dome E, constructed, combined, and arrangedsubstantially as set forth.

In testimony that I claim the foregoing as my own invention I affix mysignature in presence of two witnesses.

PATRICK MIHAN.

Witnesses:

F. P. HALE, F. G. HALE.

